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Comment by braindongle | Hacker News Reader

JS novice here. Is this an idiomatic way to conditionally perform an operation in JS? It saves typing, but if(){} is much more explicit.

  a && this.oo.push(x.V.TH);

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That's minification. The actual source code almost certainly does `if (a) { ... }`, but the minifier will shorten that into `a&&...`, thereby saving multiple bytes. Accumulate this over different if-clauses, and you're looking at serious savings.

Ah, I see. Thanks. Interesting. The minifier must be smart enough to know that you're not doing anything with the return value, since the two aren't equivalent in that respect.

  false && console.log('foo');  //false
  if(false){ console.log('foo') }; //undefined

Not for user-written code, but most websites run their Javascript through tools to condense it so that the download size is smaller.

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